In automotive and other fields, quick connector couplings are often utilized to provide a fluid connection between two components or conduits, thus establishing a fluid line between the two components, usually a rigid tube and a system element contained within a metal housing. Use of quick connector couplings is advantageous in that a sufficiently sealed and secured fluid line may be established with a minimum amount of time and expense.
Check valves are traditionally pressure, rather than tube, activated. A pressure activated check valve is illustrated in U.S. Pat. No. 5,107,890, to Gute. Pressure activated check valves allow flow only in one direction. One-directional flow may be preferable and even necessary in some systems. Pressure activated check valves are thus suitable and perhaps desirable for use in such systems. In systems where two-directional flow is desired, however, a pressure activated check is not sufficient.
Tube activated check valves typically permit two-directional flow through a coupling. Examples of tube activated check valves are found in U.S. Pat. No. 5,273,254, to McNaughton, and in U.S. Pat. 4,936,544 to Bartholomew. Prior tube activated valves, while permitting bi-directional flow, have not always reliably checked flow when the coupling is in an unsealed state.
A need exists for a tube activated check valve which permits two-directional fluid flow when the coupling is sealed, that is, when a tube is present, but reliably checks flow through the coupling when the coupling is unsealed, that is, when a tube is not present. The check valve of the present invention addresses this need.